Plant building for an installation and method for operating a plant building

ABSTRACT

A plant building includes a purification chamber and a pump chamber with a pump for cooling water. The pump chamber directly adjoins the purification chamber and the geometry of the pump chamber is such that disturbing swirls are avoided while the installation is in operation, due to the high speed of the coolant. The direct proximity of the two chambers to each other results in lower cost due to the elimination of the usual steadying zones.

This application is the national phase under 35 U.S.C. §371 of PCTInternational Application No. PCT/DE01/00139 which has an Internationalfiling date of Jan. 15, 2001, which designated the United States ofAmerica and which claims priority on Patent Application No. DE 100 03517.5 filed Jan. 27, 2000, the entire contents of which are herebyincorporated by reference.

FIELD OF THE INVENTION

The invention generally relates to an operations building for a plant,in particular for a power-generation plant, which has a pump chamber anda cleaning chamber for cooling water. The invention also generallyrelates to a method of operating the operations building.

BACKGROUND OF THE INVENTION

In an industrial plant, in particular in a power station for generatingpower, cooling water is necessary for operating the plant. A typicalexample for the use of cooling water is the cooling of steam in acooling tower of a power station. In this case, the cooling water isgenerally removed from a natural reservoir, for example from a river orlake, and is first of all cleaned in the cleaning chamber in order thento be sent to plant components via the pump chamber, by a pump arrangedtherein. In large-scale plants, the delivery capacity of the pumpingsystem is a number of cubic meters of cooling water per second. The flowpaths, the cleaning arrangements for cleaning the cooling water, thepump chamber and, in particular, the pump are of correspondinglyvoluminous design. The behavior of the cooling liquid flowing into thepump is decisive for reliable and permanent disruption-free operation ofthe pump. In particular an as far as possible vortex-free flow into thepump is necessary for this purpose.

In terms of design, the cleaning chamber and the outlet cross sectionthereof are usually very narrow and high, whereas the pump chamber,which is arranged downstream of the cleaning chamber in terms of flow,is wide and flat and designed, for example, as a covered pump chamber.These extremely different chamber geometries and internals in thecleaning chamber, or downstream of the same as seen in the flowdirection, cause turbulence in the cooling liquid. In order to preventsaid turbulence or vortices resulting in the formation of surface orbase vortices which are disruptive for the pump, a calming section isusually provided between the cleaning chamber and the pump chamber. Thecalming section requires a not inconsiderable amount of space, whichadversely affects the costs during the production of the operationsbuilding.

The book by Lueger “Lexikon der Technik” [Lexicon of technology] 4thedition; volume 6; Lexikon der Energietechnik und Kraftmaschinen[Lexicon of power engineering and prime movers], A-K, edited by Rudolfvon Miller, Deutsche Verlags-Anstalt GmbH, Stuttgart, 1965, pages666-667 and pages 669-670, discloses an operations building for apower-generation plant. The operations building has a pump chamber forarranging a pump for cooling water and also a cleaning chamber. Theoperations building is designed as an intake structure on a free body ofwater with a number of intake chambers such that the water flows to theindividual intake chambers uniformly and as far as possible in avortex-free manner, and that the bottom of the body of water is notswirled up or adversely affected by the inflowing water.

The article entitled “Pumping stations and heavy duty raw water pumpsfor the cooling of industrial complexes and power plants” by Courcot,P., Goudy, G. and Lapray, J. F.; GEL Alstom Technical Review No.12-1993; Paris; ISSN: 1148-2893, discloses a pump arrangement in whichit is possible to dispense with an otherwise conventional calmingsection between the cleaning chamber and the pump chamber, a rotatingscreening arrangement nevertheless being provided exclusively. In thecase of this prior art, in particular the formation of disruptivevortices in the cooling-water stream is not reliably avoided.

SUMMARY OF THE INVENTION

An object of an embodiment of the invention is to specify an operationsbuilding for a plant, and a method of operating an operations building,which ensure reliable plant operation with low plant-production costs.

The operations-building-related object may be achieved according to anembodiment of the invention by the operations building having a pumpchamber for arranging a pump for cooling water and also a cleaningchamber, the pump chamber directly adjoining the cleaning chamber, itbeing the case that the pump chamber is connected to the cleaningchamber via an intake opening, which is adjoined by a wall region whichruns obliquely in relation to the chamber side wall, and the flow crosssection for the cooling liquid flowing into the pump chamber is taperedby means of a pump installed in the pump chamber, with the result thatthe cooling liquid, in order to avoid disruptive vortices, has a flowspeed of approximately 2 to 3 m/s.

An embodiment of the invention takes as its departure point here, thesurprising finding that the cleaning chamber may be arranged immediatelyin front of the pump chamber, that is to say that the conventionalcalming sections may be dispensed without disruptive vortices, inparticular surface vortices, occurring in the pump chamber. This isbecause the vortices can be avoided by said expedient geometricalconfiguration of the pump chamber which results in a comparatively highflow speed. This relationship between the flow speed and vorticeformation is surprising since, up until now, it has been assumed thatsuccess is only achieved in precisely the opposite way, that is to saythe lowest possible speed should be set in order to avoid vortices. Thelevel of a sufficient flow speed depends on a number of factors, inparticular also on the quantity of cooling liquid which is to be pumped.In industrial plants with a pumping capacity of a number of cubic metersper second, a flow speed of approximately 0.5 m/s has been provided upuntil now in the calming section. In order to avoid the vortices, ahigher flow speed than this, in particular of approximately between 2-3m/s, is set.

One decisive advantage of this configuration is that the absence of thecalming section results in the overall volume of the operations buildingbeing reduced and thus in the production costs for the operationsbuilding being reduced to a considerable extent.

The chamber geometry may be configured such that, during operation, theflow speed of the cooling liquid is increased as it passes into the pumpchamber.

In conventional plants and in the plant described here, the flow speedsfor the cooling water within a cleaning machine arranged in the cleaningchamber are approximately 1 m/s. Whereas, in conventional plants, thisflow speed is reduced to approximately 0.5 m/s through the calmingsections at the inflow to the pump chamber, the present embodiment, incontrast, provides an increase in the speed in order to form asufficiently high flow speed.

An intake opening via which the cooling water flows into the pumpchamber is adjoined by a wall region which runs obliquely in relation tothe chamber side wall. This avoids backflow spaces in the pump chamber,which are a typical cause of the formation of vortices.

In a particularly preferred embodiment, the pump chamber is designed forsuch positioning of the pump that, by the displacing action of a pumptube, separation of the flow from the wall is reliably prevented despitethe usually large expansion angle in the inflow region of the pumpchamber.

With the pump installed, the flow cross section for the cooling liquidflowing into the pump chamber tapers. It is possible here for thediameter of the pump tube to vary over a large range, with the resultthat both pumps with a small tube diameter and high impeller speed andpumps with a large tube diameter and low impeller speed can be insertedinto the same chamber. The tube diameter and the impeller speeds areselected here so as to achieve a low-level so-called “necessary netpositive suction head” (NPSH) for avoiding the so-called cavitation,that is to say the formation and the abrupt bursting of steam bubbles.For this purpose, in particular the distance between the axial center ofthe pump and the chamber rear wall and the distance between the base andthe pump suction bell are designed as a function of the suction-belldiameter and of the size of the chamber.

In order to avoid wall and base vortices and to achieve an acceptablespeed profile in the pump tube, in preferred embodiments the pumpchamber has as an alternative, and preferably in combination, thefollowing features:

a directing sill, running approximately perpendicularly to the inflowdirection of the cooling water, on the chamber base in the region of thepump, said sill serving, in particular, for deflecting the flow in thedirection of the pump;

a longitudinal sill, arranged on the chamber base and runningapproximately in the direction of the inflow direction, as flowresistance for base vortices;

a continuation of the longitudinal sill on the chamber rear wall as, inparticular, a vertically running wall sill;

a spacing of the wall sill from a chamber ceiling of the pump chamber,which is designed as a covered pump chamber, in order, for avoidingvortices, to ensure sufficient flow around the pump;

the chamber side walls, as in the intake region, merge into the rearchamber walls via obliquely running wall regions.

The chamber base is beveled in relation to the chamber rear wall.

Longitudinal plates, running in particular perpendicularly to thechamber base, are arranged in the intake opening to the pump chamber.

If required, the interior of the pump chamber is accessible from theoutside via a flow-connection, which is used for further removal ofcooling water or also for measuring coolant properties. Cooling-waterremoval is provided, for example, for extinguishing purposes or fortemporary cleaning purposes by means of cooling water. To this end,pumps are usually arranged in the pump chamber or in the calmingsection. These act, however, as flow resistance and are often the causeof the formation of surface vortices. With the flow-connection via thechamber wall, there is no longer any need for the arrangement of suchpumps in the interior.

If use is made of so-called tubular type pumps, in which the pump tubeis guided through a chamber ceiling of the pump chamber, it is possible,additionally or alternatively, for relatively large quantities ofadditional water to be withdrawn above the chamber ceiling. This waterleaves the pump chamber through an annular gap between the pump tube andchamber ceiling.

In addition to the specific provisions made in the pump chamber itself,preferred developments also provide for vortex-avoiding and flow-calmingand flow-evening measures, which contribute to evening out the flow, tobe taken in the cleaning chamber. For this purpose, the cleaningchamber, like the pump chamber, has obliquely running side walls in theintake region to the pump chamber. Furthermore, a cleaning arrangementis arranged preferably immediately in front of the intake opening of thepump chamber and fully encloses the same. The cleaning arrangementpreferably has a flow-directing plate on its side which is directed awayfrom the pump chamber.

An alternative embodiment is preferably formed by designing the pump asa concrete spiral casing pump, the concrete spiral casing forming thechamber ceiling of the pump chamber. The concrete spiral casing pumphere preferably has a suction tube which projects into the pump chamber.

In order to achieve the method-related object, an embodiment of theinvention makes provision, in an operations building having a pumpchamber and a pump for cooling water arranged therein, and having acleaning chamber directly adjacent to the pump chamber, for the coolingwater to be cleaned in the cleaning chamber and then to flow into thepump chamber at a flow speed of approximately 2 to 3 m/s, with theresult that disruptive vortices are avoided.

The advantages given in respect of the operations building and preferredembodiments can be transferred analogously to the method.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the invention are explained in more detailhereinbelow with reference to the drawings, in which, in schematicillustrations in each case:

FIG. 1 shows, in detail form, a lateral illustration in section throughan operations building,

FIG. 2 likewise shows, in detail form, a lateral illustration in sectionthrough an operations building with a concrete spiral casing pump, and

FIG. 3 shows a plan view of a horizontal section through a pump chamber.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

According to FIGS. 1 and 2, an operations building 2 for an, inparticular, industrial plant, for example a power station for generatingpower, has a pump chamber 4 and a cleaning chamber 6, which are directlyadjacent to one another via a common chamber wall 8. The cleaningchamber 6 and the pump chamber 4 are in flow-connection with one anothervia an intake opening 10. The pump chamber 4 is designed as a so-calledcovered pump chamber and has a chamber ceiling 28. Arranged in the pumpchamber 4 is a pump 14 which is spaced apart from the chamber base 12and has a pump tube 16. The latter is guided through the chamber ceiling28, an annular gap 29 being formed in the process. In the pump chamber4, a suction bell 17 adjoins the pump tube 16 on the end side.

Unlike the conventional separate pump 14 according to FIG. 1, the pumpaccording to FIG. 2 is designed as a concrete spiral casing pump 14 a.The latter has a concrete spiral casing which is formed by concretecomponents 19 positioned in the building structure or by the buildingstructure itself. From the concrete spiral casing pump 14 a, a suctiontube 20, with suction bell 17 provided on the end side, extends into thepump chamber 4, with the result that the suction bell 17 is at a levelwhich is favorable for operation.

Arranged in the cleaning chamber 6, immediately in front of the intakeopening 10 and covering over the latter completely, is a cleaningarrangement for the cooling water in the form of a filter or of ascreening arrangement 22. It is designed, in particular, as a so-calledbelt screen machine. The latter has a circulating belt screen with aplurality of screen surfaces 24, which serve for cleaning cooling waterin the region of the intake opening 10 and are cleaned in the top regionof the belt screen machine, for example, by jets. The screeningarrangement 22 preferably has further cleaning arrangements (notillustrated specifically) arranged upstream of it.

The cooling water is usually removed from an natural reservoir, passes,via an inflow opening 26, into the cleaning chamber 6, is cleaned thereand is then taken in through the intake opening 10 into the pump chamber4 by the pump 14. The operations building 2 is arranged, in relation tothe water level of the reservoir, such that, with a natural fluctuationof the water level between a high water level H and a low water level N,the suction bell 17, that is to say the inflow region of the pump 14, issufficiently covered over with cooling water. This is because, if thecovering-over level is too low, the quality of the flow in the pump tube16 is impaired. This applies, in particular, when the water level dropsbelow the chamber ceiling 28. This situation is thus admissible only forspecific operating cases and for a limited period of time, for exampleduring start-up of the pump 14, when the water is fed to the operationsbuilding 2 through a long channel or a long pipeline. A sufficientlyhigh covering-over level, in addition, helps to avoid the so-calledcavitation, that is to say the formation and abrupt bursting of steambubbles to form a pressure wave which adversely affects the material.The illustrated design of the pump chamber 4 as a covered pump chamberwith the chamber ceiling 28 counteracts the production of surfacevortices.

The specific provisions made in order to avoid vortices are explainedhereinbelow with reference to FIGS. 1 and 3. As can be gathered fromFIG. 3, the wall region 30, which adjoins the intake opening 10, runsobliquely in relation to the chamber side wall 32 which, in turn, mergesinto the chamber rear wall 34 via a rear, oblique wall region 30 a.Arranged on the chamber base 12 is a directing sill 36 and alongitudinal sill 38, which have a triangular cross-sectional surfaceand are arranged in relation to one another to form a cross. In thiscase, the longitudinal sill 38 runs in the inflow direction 40 of thecooling water.

The directing sill 36 serves primarily for deflecting the cooling liquidinto the pump 14. For this purpose, as can be gathered from FIG. 1, itis preferably arranged some way in front of the pump axis 42. Thedirecting sill 36 and the longitudinal sill 38 may have the same profileor different profiles and/or different dimensions. The longitudinal sill38 serves for preventing base vortices. It is continued in a wall sill44, which extends vertically upwards on the chamber rear wall 34 but isspaced apart from the chamber ceiling 28 in order to allow sufficientflow of cooling liquid around the pump 14. The wall sill 44 servesessentially for easier deflection of the flowing cooling liquid to thepump.

In the rear region of the pump chamber 4, the chamber base 12 is beveledin relation to the rear wall regions 30 a and to the chamber rear wall34 via a corner compensating means 46, which is illustrated by dashedlines in FIG. 1. This serves for improving the deflection of the baseflow and reduces the degree of turbulence of the flow in this region. Ingeneral terms, the pump chamber 4 is distinguished in that, despite theuse of planar boundary surfaces, it does not change the flow abruptlyand this, despite the unusually high speed, achieves a low degree ofturbulence in the pump tube 16. By virtue of the arrangement of bevelsin the critical regions, the pump chamber 4 may thus be referred to asbeing largely edge-free. The typical flow paths of the cooling liquidare illustrated in the figures by dashed arrow lines. A comercompensating device in the base region of the intake opening 10 isdispensed with according to FIG. 1 since, there, a stable flow vortex 48forms of its own accord, said flow vortex acting as a so-called“hydraulic ball bearing” in the manner of a stable roller, with theresult that the rest of the flow flows over the flow vortex 48 in anessentially unaffected manner. The flow vortex 48 may be reduced, forexample, by moderate beveling of the base region of the intake opening10.

In particular the oblique front wall region 30 avoids separation of theflow from the chamber wall. This is achieved not least by thedisplacement action of the pump tube 14, which is decisively determinedby the size and the position of the pump 14 in relation to the wallregions 30. In particular there is a reduction in the flow cross sectionfor the cooling liquid following the intake opening 10, with the resultthat there is an increase in the flow speed. This prevents separation ofthe flow and thus already helps to avoid vortices. On account of thehigh speed of the flow, in addition, the situation where no inparticular stationary flow vortices form on the surface is achieved in astraightforward and reliable manner. This is because such stationaryflow vortices only form stably when there is sufficiently calm flow.Herein resides precisely the essential feature of the chamber geometryby way of which such comparatively calm flow is avoided. With the normalwater level N, the chamber ceiling 28 results in an improvement in thespeed distribution in the pump tube 16.

In order effectively to prevent disruptions from the screeningarrangement 22 in the particularly critical region in the transitionbetween the cleaning chamber 6 and pump chamber 4, in this caselongitudinal plates 50, which are aligned essentially perpendicular tothe chamber base 12, are provided. For a suitable flow guidance, inaddition, the side walls 52 of the cleaning chamber 6 are beveled inrelation to the intake opening 10. Furthermore, at its end which isdirected away from the intake opening 10, the screening arrangement 22has flow-directing plates 54 which are arranged on the borders on thefront side of the screening arrangement 22 in a rectilinear manner or atan oblique angle in relation to said screening arrangement.

In the chamber wall 8, preferably in the region of the wall region 30,flow-connections 56 to the interior of the pump chamber 4 are provided.Cooling water may be removed from the pump chamber 4 via saidconnections without pumps which adversely affect the coolant flow havingto be introduced into the interior of the pump chamber 4. Via theflow-connection 56, it is also possible to take measurements, such as afilling-level measurement, without the flow in the pump chamber 4 beingaffected. Alternatively or additionally, in the exemplary embodimentaccording to FIG. 1, that is to say with the use of a so-called tubulartype pump, it is possible to remove a relatively large quantity ofcooling water. In this case, the cooling water flows through the annulargap 29 between the chamber ceiling 28 and pump tube 16.

The formation both of base vortices and of surface vortices is reliablyavoided by the measures described above. The decisive factor for this isthe high speed in the pump chamber 4. In addition to the essentialadvantage of dispensing with the calming section, the pump chamber 4, inaddition, can be operated reliably with the pump 14 being covered overby cooling water to a comparatively low extent. This is because the riskof surface vortices forming is considerably reduced in relation toconventional configurations. Even if the water level falls below the lowwater level N to a reduced water level R, which occurs under somecircumstances, for example, during start-up and may drop below the levelof the chamber ceiling 28, the cooling-water flow in the pump chamber 4is sufficiently stable. The necessary covering-over level is thusdetermined essentially just by the cavitation problem. On account of thereduced covering-over level, the necessary overall height of theoperations building 2 is reduced, with the result that the productioncosts can be kept low.

The invention being thus described, it will be obvious that the same maybe varied in many ways. Such variations are not to be regarded as adeparture from the spirit and scope of the invention, and all suchmodifications as would be obvious to one skilled in the art are intendedto be included within the scope of the following claims.

What is claimed is:
 1. An apparatus, comprising: a pump chamber forarranging a pump for cooling liquid, and a cleaning chamber, wherein thepump chamber is connected to the cleaning chamber via an intake opening,adjoined by a wall region which runs obliquely in relation to a sidewall of the pump chamber, and wherein a flow cross section for coolingliquid flowing into the pump chamber is tapered in the pump chamber,resulting in the cooling liquid having a flow speed of approximately 2to 3 m/s.
 2. The apparatus as claimed in claim 1, wherein a chamber baseof the pump chamber includes a directing sill, running approximatelyperpendicularly to the inflow direction of the cooling liquid, in aregion of the pump for deflecting the flow in the direction of the pump.3. The apparatus as claimed in claim 1, wherein a chamber base of thepump chamber includes a longitudinal sill, running approximately in thedirection of the inflow direction of the cooling water, as flowresistance for base vortices.
 4. The apparatus as claimed in claim 3,wherein the longitudinal sill is continued on a rear wall of the pumpchamber as a wall sill.
 5. The apparatus as claimed in claim 4, whereinthe pump chamber is designed as a covered pump chamber with a chambercover, and wherein the wall sill is spaced apart from the chamber cover.6. The apparatus as claimed in claim 1, wherein the chamber side wallsof the pump chamber merge into the chamber rear wall of the pump chambervia obliquely running rear wall regions.
 7. The apparatus as claimed inclaim 1, wherein a chamber base in a rear region of the pump chamber isbeveled in relation to the chamber wall.
 8. The apparatus as claimed inclaim 1, wherein longitudinal plates are arranged in the intake opening.9. The apparatus as claimed in claim 1, wherein an interior of the pumpchamber is accessible via a flow-connection.
 10. The apparatus asclaimed in claim 1, wherein the pump chamber includes a chamber ceilingthrough which a pump tube is guided, an annular gap being formed in theprocess, with the result being that cooling water can be withdrawn fromthe pump chamber via the annular gap.
 11. The apparatus as claimed inclaim 1, wherein the cleaning chamber includes obliquely running sidewalls in the region oriented toward the pump chamber.
 12. The apparatusas claimed in claim 1, wherein, in the cleaning chamber, a cleaningarrangement is arranged immediately in front of the intake opening. 13.The apparatus as claimed in claim 12, wherein a flow-directing plate isprovided on the cleaning arrangement.
 14. The apparatus as claimed inclaim 1, wherein the pump is designed as a concrete spiral casing pump,the concrete spiral casing forming a chamber ceiling of the pumpchamber.
 15. An operations building for a plant comprising the apparatusas claimed in claim
 1. 16. The operations building of claim 15, whereinthe plant is a power-generation plant.
 17. The apparatus as claimed inclaim 1, wherein the cooling liquid flow speed is controlled in order toavoid disruptive vortices.
 18. The apparatus as claimed in claim 17,wherein a chamber base of the pump chamber includes a directing sill,running approximately perpendicularly to the inflow direction of thecooling liquid, in a region of the pump for deflecting the flow in thedirection of the pump.
 19. The apparatus as claimed in claim 17, whereina chamber base of the pump chamber includes a longitudinal sill, runningapproximately in the direction of the inflow direction of the coolingwater, as flow resistance for base vortices.
 20. The apparatus asclaimed in claim 19, wherein the longitudinal sill is continued on arear wall of the pump chamber as a wall sill.
 21. The apparatus asclaimed in claim 6, wherein the chamber base in a rear region of thepump chamber is beveled in relation to the chamber wall.
 22. Theapparatus as claimed in claim 19, wherein, in the cleaning chamber, acleaning arrangement is arranged immediately in front of an intakeopening to the pump chamber.
 23. The apparatus as claimed in claim 22,wherein a flow-directing plate is provided on the cleaning arrangement.